Process of producing a metal of high grade from a metal of low grade.



UNITED STATES PriTENT OFFICE.

LEWIS A. LnoNAnn, or NEW roan, AND-JESSE r, LAammna, or BROOKLYN,

' new YORK.

rnocnss or rnonucme A METAL or HIGH GRADE mom A mn'r I. or LOW e'nAnn.

970,728. Specification of Letter! Patent Patented Sept. 20, 1910. No Drawing. Application filed September 17, 1909. Serial No, 518,152.

To all whom it may concern: in which the pieces of metal are embedded Be it known that we, LEWIS A. LEONARD, a and which comprises a suitable substance or citizen of the United States, and a resident substances which so act upon or co-act with of New York city, in the county and State the steel during the bakm step that the v of New York, and Jesse P. LARRIMER, a metal is conditioned or ren' ered susceptible citizen of the United States,and a' resident to the action of the subszguent step or steps of Brooklyn, in the county of and of the process. The l) y of material in State of New York, have invented certain which we prefer to bake, in an air-tight box new and useful Improvements in Processes or holder, the pieces of steel comprises hyof Producino a Metal of Hi h Grade from drated oxid of iron, silica and a small pera Metal of ow Grade, of which the folcentage of phosphorus, there being approxilowing is a specification. mately about 25% 9f hydrated oxid of iron The invention relates to improvements in and approximately about of silica. the art of producin a high grade steel from The percenta e of phosphorus may be 15 a low grade of steel.

Our invention pertains to methods of portions mentioned may, of course, vary treating low grade steel whereby without re with the thoroughness with which the rocducing the same to a molten state or changess may be carried out. We have use the ing its material shape or proportions, we materials named in about the proportions 20 very greatly improve and change the char stated with entire success in the treatment of 75 actor of the same, the low grade steel, su'cb steel. We have found that the ingredients as a steel which runs from nine to twelve just named and in about the proportions points of carbon, being converted into :1 hi h given are present in some low grades of iron grade of steel adapted-for lathe tools, chise s, ore which we have used with entire satisfac- 2 vault plates and the like. tion in carrying out our process, and while The invention comprises methods whereby we prefer to use the substances as found in the quality of steel, whether the same be in nature, we do not wish to confine our inventhe form of bars, sheets, or other commercial tion to such use, nor to the specific in edishapes, may be very greatly improved and cuts named. The pieces of steel embed ed in 30 the degree of hardness and toughness imthe material indicated and confined within a 5 parted to the steel varied as the conditions closed box or holder, are baked in a retort or circumstances of its intended use may reof usual or any suitable construction at a quire. uniform heat for from about three to about Our invention comprises as one important fifteen hours, the time varying with the 35 feature, the treatment of a piece of steel thickness of the pieces and the degree of without reducing it to a molten state, wherethoroughness with which it may be desired by the steel becomes conditioned for the to carry out the process, and the degree of further step or steps of the process in which heat employed being sufiicient to bring the it is subjected to the action of carboniferous pieces to and maintain them at about a 40 material, such carboniferous substance being cherry-red color or from about six hundred first, burnt leather, or burnt bone, or other to eight hundred degrees Fahrenheit accordhighly carboniferous material within a bed ing to the character and thickness of the of which the steel is subjected to a baking pieces. The effect of the baking of the pieces process, and second, an element or elements of steel is that the steel becomes transformed immersed or quenched for a periodvarying affected by the further step or steps of the with the degree of hardness or toughness reprocess. quired. After the baking process or ste herein- The first step in the treatment of the steel before described has been complete the steel 50 for its conversion into a higher grade is to is removed from the box or holder in which condition the steel for the further step or it was baked and packed in asimilar box steps of cur process, and in carr ing out or holder with some highly carboniferous this first step of the rocess we sr. ject the material, such as burnt leatherand burnt pieces of steel to a ba ring in a closed metal bone, and subjected to a further baking for box or holder containing a body of material a period of about one-half of that bccupied about one-hal of one per cent. The pro- 7 45 in a cold bath in which the steel, then hot, 18 or conditioned to readily yield to or become 9 I closed hol in the first baking, the heat beingsuflicie'nt to maintain the steel at about a cherry-red color, as in the first baking. The steel .is preparedby the first step of the process to '5 eagerly, and efiiciently take up or become .afi'ectedby the carbon in the second step of the process, and-after said-second step has been completed the steel is quenched ina cold bath of water in which has been incorporated material suitable .for; hardening or toughening the same, such bath .containing, for illustration, sulfate oflime, preferably granulated, and "ferric oxid mixed with powdered charcoal, other carboniferous' ferred proportions of about ten per cent. of the c'a rboniferousmaterial to the bath-until the latter can act through the .thicknessofthe hardened throughout to. a: remarkable depiece, the latter becomes gree and becomes converted or changed from Our invention renders it entirely prac ticable to harden pieces of steel. throughout to'a maxnnrnn degree, or to vary the degree and depth of the hardening as circumstances of our process is that by it thoroughlyv convert or transform steel from a low grade to arsteel of high grade and that The result heretofore by any processes known to us.

' What we claim as our invention and desire secure by Letters Patent,-is: I Y j ,19 1. A process of treat-ing'steel for convertsing it from a low rade to a high grade, which com rises the aking of the steel in a er in the presence of a substance ground burnt bone or material, in the preninety per cent. of the-ferric oxid, by Weight. The propor -a-steelof lowgrade to a steel of high grade.

T at th'esametime we may secure a degreeof hardness extending entirely through the metal notattained avers preparing the metal to be successfully acted on-by carbon, and then subjecting the steel toa baking in the presence of carboniferous material, and finally quenching the steel in abath. i r

2. A process oftreating steel for converting itfrom a low grade-to a high grade, which comprises the baking of the steel in a closed holder in the presence of a substance preparing the metal to be successfully acted on. by carbon, v to a baking in the presence of carboniferous materiahand'finally quenching the steel in a bath containing sulfate oftliine and ferric oxid mixed withcarboniferous material. '3. Aprocess of treating steel for converting it from a loW rade to a high grade which-comprises the aking of the steel in a closed holder in the presence of hydrated oxid of iron and silica, steel to .a' baking in the presence of carboniferous material, and finally quenching the steel in a bath.

4. A process of treating steel for converting it from a low grade to a high grade which comprises the baking of thesteel in a closed holder in the presence of hydrated and then subjecting the steel I then subjecting the v oxid of iron and silica, then subjecting the steel to a bakin I in the presence of carboniferous materia and finally quenching the ferric 'oiiid and carboniferous material, I

5. A process of treating steel for converting it from alow gradeto a'higlr-grade which comprises the' baking of the steel in a closed holder in the presenceof hydrated oxid of iron, silica and phosphorus, then subjectingthe steel to a baking'in' the presenceof carboniferous material, and finally quenching thesteelin a'bath;

Signed, at N ew New York and State of New York, this 16th day of September, A. D., 1909. r LEWIS A. LEONARD. j V JESSE P. LARRIMER.

Witnesses:

' ARTHUR MARION,

CHAS. C. GILL.

York city,'in the county of 

